The subject invention relates to novel antimicrobial compounds, their compositions and their uses.
The chemical and medical literature describes compounds that are said to be antimicrobial, i.e., capable of destroying or suppressing the growth or reproduction of microorganisms, such as bacteria. For example, such antibacterials and other antimicrobials are described in Antibiotics, Chemotherapeutics and Antibacterial Agents for Disease Control (M. Grayson, editor, 1982), and E. Gale et al., The Molecular Basis of Antibiotic Action 2d edition (1981).
The mechanism of action of these antibacterials vary. However, they are generally believed to function in one or more of the following ways: by inhibiting cell wall synthesis or repair; by altering cell wall permeability; by inhibiting protein synthesis; or by inhibiting synthesis of nucleic acids. For example, beta-lactam antibacterials act through inhibiting the essential penicillin binding proteins (PBPs) in bacteria, which are responsible for cell wall synthesis. As another example, quinolones act, at least in part, by inhibiting synthesis of DNA, thus preventing the cell from replicating.
The pharmacological characteristics of antimicrobials, and their suitability for any given clinical use, vary. For example, the classes of antimicrobials (and members within a class) may vary in 1) their relative efficacy against different types of microorganisms, 2) their susceptibility to development of microbial resistance and 3) their pharmacological characteristics, such as their bioavailability, and biodistribution. Accordingly, selection of an appropriate antibacterial (or other antimicrobial) in a given clinical situation requires analysis of many factors, including the type of organism involved, the desired method of administration, the location of the infection to be treated and other considerations. there is a continuing need for broad spectrum antimicrobials, which are effective against resistant microbes.
Some 1,4-dihydroquinolone, naphthyridine or related heterocyclic moieties are known in the art to have antimicrobial activity and are described in the following references: R. Albrecht, Prog. Drug Research, Vol. 21, p. 9 (1977); J. Wolfson et al., xe2x80x9cThe Fluoroquinolones: Structures, Mechanisms of Action and Resistance, and Spectra of Activity In Vitroxe2x80x9d, Antimicrob. Agents and Chemother., Vol. 28, p. 581 (1985); G. Klopman et al., Antimicrob. Agents and Chemother., Vol. 31, p. 1831 (1987); M. P. Wentland et al., Ann. Rep. Med. Chem., Vol. 20, p. 145 (1986); J. B. Cornett et al., Ann. Rep. Med. Chem., Vol. 21, p. 139 (1986); P. B. Fernandes et al., Ann. Rep. Med. Chem., Vol. 22, p. 117 (1987); A. Koga, et al., xe2x80x9cStructure-Activity Relationships of Antibacterial 6,7- and 7,8-Disubstituted 1-alkyl-1,4-dihydro-4-oxoquinoline-3-carboxylic Acidsxe2x80x9d, J. Med. Chem., Vol. 23, pp. 1358-1363 (1980); J. M. Domagala et al., J. Med. Chem., Vol. 31, p. 991 (1988); T. Rosen et al., J. Med. Chem., Vol. 31, p. 1586 (1988); T. Rosen et al., J. Med. Chem., Vol. 31, p. 1598 (1988); B. Ledoussal et al., xe2x80x9cNon 6-Fluoro Substituted Quinolone Antibacterials: Structure and Activityxe2x80x9d, J. Med Chem., Vol. 35, p. 198-200 (1992); J. M. Domagala et al., xe2x80x9cQuinolone Antibacterials Containing the New 7-[3-(1-Aminoethyl)-1-pyrrolidinyl] Side Chain: The Effects of the 1-Aminoethyl Moiety and Its Stereochemical Configurations on Potency and in Vivo Efficacyxe2x80x9d, J. Med. Chem., Vol. 36, pp. 871-882 (1993); Hagen et al., xe2x80x9cSynthesis and Antibacterial Activity of New Quinolones Containing a 7-[3-(1-Amino-1-methylethyl)-1-pyrrolidinyl] Moiety. Gram Positive Agents with Excellent Oral Activity and Low Side-Effect Potentialxe2x80x9d, J. Med. Chem. Vol. 37, pp. 733-738 (1994); V. Cecchetti et al., xe2x80x9cStudies on 6-Aminoquinolines: Synthesis and Antibacterial Evaluation of 6-Amino-8-methylquinolonesxe2x80x9d, J. Med. Chem., Vol. 39, pp. 436-445 (1996); V. Cecchetti et al., xe2x80x9cPotent 6-Desfluoro-8-methylquinolones as New Lead Compounds in Antibacterial Chemotherapyxe2x80x9d, J. Med. Chem., Vol. 39, pp. 4952-4957 (1996); Hong et al., xe2x80x9cNovel 5-Amino-6-methylquinolone Antibacterials: a New Class of Non-6-fluoroquinolonesxe2x80x9d, Bioorg. of Med. Chem. Let., Vol. 7, pp. 1875-1878 (1997); U.S. Pat. No. 4,844,902 to Grohe on Jul. 4, 1989; U.S. Pat. No. 5,072,001 to Hagen and Suto on Dec. 10, 1991; U.S. Pat. No. 5,328,908 to Demuth and White on Jul. 12, 1994; U.S. Pat. No. 5,457,104 to Bartel et al. on Oct. 10, 1995; U.S. Pat. No. 5,556,979 to Philipps et al. on Sep. 17, 1996; European Patent Appl. 572,259 of Ube Ind. pub. Dec. 1, 1993; European Patent Appl. 775,702 of Toyama Chem. Co. pub. May 28, 1997; Japanese Patent Pub. 62/255,482 of Kyorin Pharm. Co. pub. Mar. 1, 1995.
Examples of bacterial infections resistant to antibiotic therapy have been reported in the past; they are now a significant threat to public health in the developed world. The development of microbial resistance (perhaps as a result of the intense use of antibacterials over extended periods of time) is of increasing concern in medical science. xe2x80x9cResistancexe2x80x9d can be defined as existence of organisms, within a population of a given microbial species, that are less susceptible to the action of a given antimicrobial agent. This resistance is of particular concern in environments such as hospitals and nursing homes, where relatively high rates of infection and intense use of antibacterials are common. See, e.g., W. Sanders, Jr. et al., xe2x80x9cInducible Betalactamases: Clinical and Epidemiologic Implications for Use of Newer Cephalosporinsxe2x80x9d, Reviews of Infectious Diseases, p. 830 (1988).
Pathogenic bacteria are known to acquire resistance via several distinct mechanisms including inactivation of the antibiotic by bacterial enzymes (e.g., b-lactamases hydrolyzing penicillin and cephalosporins); removal of the antibiotic using efflux pumps; modification of the target of the antibiotic via mutation and genetic recombination (e.g., penicillin-resistance in Neiserria gonorrhoeae); and acquisition of a readily transferable gene from an external source to create a resistant target (e.g., methicillin-resistance in Staphylococcus aureus). There are certain Gram positive pathogens, such as vancomycin-resistant Enterococcus faecium, which are resistant to virtually all commercially available antibiotics.
Hence existing antibacterials have limited capacity in overcoming the threat of resistance. Thus it would be advantageous to provide quinolones with useful properties that can be used against resistant microbes.
Applicants have found a novel series of quinolones and related compounds that are effective against resistant microbes, and provide significant activity advantages over the art. In particular, the invention relates to compounds having a structure according to Formula (I) 
wherein:
(A)
(1) A1 is selected from xe2x80x94Nxe2x80x94 and xe2x80x94C(R8)xe2x80x94, where R8 is selected from hydrogen, halo, lower alkoxy, lower alkylthio, lower alkyl, lower alkene and lower alkyne;
(2)
(a) X is selected from xe2x80x94Cxe2x80x94 and xe2x80x94Nxe2x80x94, where (i) if X is xe2x80x94Cxe2x80x94, a is a double bond and b is a single bond, and (ii) if X is xe2x80x94Nxe2x80x94, a is a single bond and b is a double bond; and
(b) Y is selected from xe2x80x94N(R1)xe2x80x94 and xe2x80x94C(R1)xe2x80x94;
(c) provided that Y is N(R1) only if X is xe2x80x94Cxe2x80x94 and Y is xe2x80x94C(R1)xe2x80x94 only if X is xe2x80x94Nxe2x80x94;
(3) R1 is selected from C3 to about C6 cycloalkyl, C4 to about C6 heterocycloalkyl, lower alkyl, lower alkene, a 6-membered aryl and a 6-membered heteroaryl;
(4) R2 is hydrogen;
(5) R3 is selected from hydrogen and hydroxy;
(6) R5 is selected from hydrogen, hydroxy, amino, halo, lower alkyl, lower alkene and lower alkoxy;
(7) R6 is selected from fluoro and chloro;
(8) R7 is xe2x80x94Qxe2x80x94C(R11)(R11xe2x80x2)(R11xe2x80x3), where Q is selected from xe2x80x94Sxe2x80x94, xe2x80x94Oxe2x80x94 and xe2x80x94C(R12)(R12)xe2x80x94, where R12 and R12 are each independently selected from hydrogen and fluoro; where R11, R11xe2x80x2 and R11xe2x80x3 are each independently selected from hydrogen, hydroxy and halo; and where R11 and R12 may also both be nil, such that a double bond is formed between the respective carbon atoms;
(9) R9 and R9xe2x80x2 are each independently selected from hydrogen and alkyl, or R9 and R9xe2x80x2 join to form a heterocyclic ring containing the nitrogen atom to which they are bonded; and
(10) R10 represents the moieties on the piperidine ring other than R7 and xe2x80x94NR9R9xe2x80x2, where each R10 is independently selected from hydrogen, lower alkyl and fluoro; or
(B) if A1 is xe2x80x94C(R8)xe2x80x94, X is xe2x80x94Cxe2x80x94 and Y is xe2x80x94N(R1)xe2x80x94, then R8 and R1 can join to form a 6-membered heterocyclic ring, where R2, R3, R5, R6, R7, R8, R9, R9, R9xe2x80x2 and R10 are as described in (A): or
(C) if A1 is xe2x80x94C(R8)xe2x80x94, X is xe2x80x94Cxe2x80x94 and Y is xe2x80x94N(R1)xe2x80x94, then R1 and R2 can join to form a monocyclic or bicyclic heterocyclic ring, where R3, R5, R6, R7, R8, R9, R9xe2x80x2 and R10 are as described in (A); or
(D) if A1 is xe2x80x94C(R1)xe2x80x94, X is xe2x80x94Cxe2x80x94 and Y is xe2x80x94N(R1)xe2x80x94, then R2 and R3 can join to form a 5-membered heterocycloalkyl that is substituted with a carbonyl moiety, where R1, R5, R6, R7, R8, R9, R9xe2x80x2 and R10 are as described in (A);
or an optical isomer, diastereomer or enantiomer thereof; a pharmaceutically-acceptable salt, hydrate, or biohydrolyzable ester, amide or imide thereof. In addition, compounds incorporating the compounds of the invention, or using compounds of the invention as starting materials are also contemplated in this invention.
It has been found that the compounds of this invention, and compositions containing these compounds, are effective antimicrobial agents against a broad range of pathogenic microorganisms with advantages in low susceptibility to microbial resistance, reduced toxicity, and improved pharmacology.
I. Terms and Definitions:
The following is a list of definitions for terms used herein:
xe2x80x9cAcylxe2x80x9d is a radical formed by removal of the hydroxy from a carboxylic acid (i.e., Rxe2x80x94C(xe2x95x90O)xe2x80x94). Preferred acyl groups include (for example) acetyl, formyl, and propionyl.
xe2x80x9cAlkylxe2x80x9d is a saturated hydrocarbon chain having 1 to 15 carbon atoms, preferably 1 to 10, more preferably 1 to 4 carbon atoms. xe2x80x9cAlkenexe2x80x9d is a hydrocarbon chain having at least one (preferably only one) carbonxe2x80x94carbon double bond and having 2 to 15 carbon atoms, preferably 2 to 10, more preferably 2 to 4 carbon atoms. xe2x80x9cAlkynexe2x80x9d is a hydrocarbon chain having at least one (preferably only one) carbonxe2x80x94carbon triple bond and having 2 to 15 carbon atoms, preferably 2 to 10, more preferably 2 to 4 carbon atoms. Alkyl, alkene and alkyne chains (referred to collectively as xe2x80x9chydrocarbon chainsxe2x80x9d) may be straight or branched and may be unsubstituted or substituted. Preferred branched alkyl, alkene and alkyne chains have one or two branches, preferably one branch. Preferred chains are alkyl. Alkyl, alkene and alkyne hydrocarbon chains each may be unsubstituted or substituted with from 1 to 4 substituents; when substituted, preferred chains are mono-, di-, or tri-substituted. Alkyl, alkene and alkyne hydrocarbon chains each may be substituted with halo, hydroxy, aryloxy (e.g., phenoxy), heteroaryloxy, acyloxy (e.g., acetoxy), carboxy, aryl (e.g., phenyl), heteroaryl, cycloalkyl, heterocycloalkyl, spirocycle, amino, amido, acylamino, keto, thioketo, cyano, or any combination thereof. Preferred hydrocarbon groups include methyl, ethyl, propyl, isopropyl, butyl, vinyl, allyl, butenyl, and exomethylenyl.
xe2x80x9cAlkoxyxe2x80x9d is an oxygen radical having a hydrocarbon chain substituent, where the hydrocarbon chain is an alkyl or alkenyl (i.e., xe2x80x94Oxe2x80x94alkyl or xe2x80x94Oxe2x80x94alkenyl). Preferred alkoxy groups include (for example) methoxy, ethoxy, propoxy and allyloxy.
xe2x80x9cAlkylthioxe2x80x9d is xe2x80x94Sxe2x80x94alkyl (e.g. xe2x80x94Sxe2x80x94CH3).
Also, as referred to herein, a xe2x80x9clowerxe2x80x9d alkoxy, alkylthio, alkyl, alkene or alkyne moiety (e.g., xe2x80x9clower alkylxe2x80x9d) is a chain comprised of 1 to 6, preferably from 1 to 4, carbon atoms in the case of alkyl, alkoxy and alkylthio, and 2 to 6, preferably 2 to 4, carbon atoms in the case of alkene and alkyne.
xe2x80x9cAminoxe2x80x9d refers to a primary (xe2x80x94NH2), secondary (xe2x80x94NH(alkyl), also referred to herein as xe2x80x9calkylaminoxe2x80x9d) or tertiary (xe2x80x94N(alkyl)2,also referred to herein as xe2x80x9cdialkylaminoxe2x80x9d).
xe2x80x9cAminoalkylxe2x80x9d is an alkyl moiety substituted with an amino, alkyl amino or dialkyl amino group (e.g., xe2x80x94CH2NH2, xe2x80x94CH2CH2NH2, xe2x80x94CH2NHCH3, xe2x80x94CH2N(CH3)2).
xe2x80x9cArylxe2x80x9d is an aromatic hydrocarbon ring. Aryl rings are monocyclic or fused bicyclic ring systems. Monocyclic aryl rings contain 6 carbon atoms in the ring. Monocyclic aryl rings are also referred to as phenyl rings. Bicyclic aryl rings contain from 8 to 17 carbon atoms, preferably 9 to 12 carbon atoms, in the ring. Bicyclic aryl rings include ring systems wherein one ring is aryl and the other ring is aryl, cycloalkyl, or heterocycloakyl. Preferred bicyclic aryl rings comprise 5-, 6- or 7-membered rings fused to 5-, 6-, or 7-membered rings. Aryl rings may be unsubstituted or substituted with from 1 to 4 substituents on the ring. Aryl may be substituted with halo, cyano, nitro, hydroxy, carboxy, amino, acylamino, alkyl, heteroalkyl, haloalkyl, phenyl, aryloxy, alkoxy, heteroalkyloxy, carbamyl, haloalkyl, methylenedioxy, heteroaryloxy, or any combination thereof. Preferred aryl rings include naphthyl, tolyl, xylyl, and phenyl. The most preferred aryl ring radical is phenyl.
xe2x80x9cAryloxyxe2x80x9d is an oxygen radical having an aryl substituent (i.e., xe2x80x94Oxe2x80x94aryl). Preferred aryloxy groups include (for example) phenoxy, napthyloxy, methoxyphenoxy, and methylenedioxyphenoxy.
xe2x80x9cCarbocyclic ringxe2x80x9d encompasses both cycloalkyl and aryl moieties, as those terms are defined herein.
xe2x80x9cCarbonylxe2x80x9d is xe2x80x94C(xe2x95x90O)xe2x80x94.
xe2x80x9cCycloalkylxe2x80x9d is a saturated or unsaturated hydrocarbon ring. Cycloalkyl rings are not aromatic. Cycloalkyl rings are monocyclic, or are fused, spiro, or bridged bicyclic ring systems. Monocyclic cycloalkyl rings contain from about 3 to about 9 carbon atoms, preferably from 3 to 7 carbon atoms, in the ring. Bicyclic cycloalkyl rings contain from 7 to 17 carbon atoms, preferably from 7 to 12 carbon atoms, in the ring. Preferred bicyclic cycloalkyl rings comprise 4-, 5-, 6- or 7-membered rings fused to 5-, 6-, or 7-membered rings. Cycloalkyl rings may be unsubstituted or substituted with from 1 to 4 substituents on the ring. Cycloalkyl may be substituted with halo, cyano, alkyl, heteroalkyl, haloalkyl, phenyl, keto, hydroxy, carboxy, amino, acylamino, aryloxy, heteroaryloxy, or any combination thereof. Preferred cycloalkyl rings include cyclopropyl, cyclopentyl, and cyclohexyl.
xe2x80x9cHaloxe2x80x9d or xe2x80x9chalogenxe2x80x9d is fluoro, chloro, bromo or iodo. Preferred halo are fluoro, chloro and bromo; more preferred typically are chloro and fluoro, especially fluoro.
xe2x80x9cHaloalkylxe2x80x9d is a straight, branched, or cyclic hydrocarbon substituted with one or more halo substituents. Preferred are C1-C12 haloalkyls; more preferred are C1-C6 haloalkyls; still more preferred still are C1-C3 haloalkyls. Preferred halo substituents are fluoro and chloro. The most preferred haloalkyl is trifluoromethyl.
xe2x80x9cHeteroatomxe2x80x9d is a nitrogen, sulfur, or oxygen atom. Groups containing more than one heteroatom may contain different heteroatoms.
xe2x80x9cHeteroalkylxe2x80x9d is a saturated or unsaturated chain containing carbon and at least one heteroatom, wherein no two heteroatoms are adjacent. Heteroalkyl chains contain from 2 to 15 member atoms (carbon and heteroatoms) in the chain, preferably 2 to 10, more preferably 2 to 5. For example, alkoxy (i.e., xe2x80x94Oxe2x80x94alkyl or xe2x80x94Oxe2x80x94heteroalkyl) radicals are included in heteroalkyl. Heteroalkyl chains may be straight or branched. Preferred branched heteroalkyl have one or two branches, preferably one branch. Preferred heteroalkyl are saturated. Unsaturated heteroalkyl have one or more carbonxe2x80x94carbon double bonds and/or one or more carbonxe2x80x94carbon triple bonds. Preferred unsaturated heteroalkyls have one or two double bonds or one triple bond, more preferably one double bond. Heteroalkyl chains may be unsubstituted or substituted with from 1 to 4 substituents. Preferred substituted heteroalkyl are mono-, di-, or tri-substituted. Heteroalkyl may be substituted with lower alkyl, haloalkyl, halo, hydroxy, aryloxy, heteroaryloxy, acyloxy, carboxy, monocyclic aryl, heteroaryl, cycloalkyl, heterocycloalkyl, spirocycle, amino, acylamino, amido, keto, thioketo, cyano, or any combination thereof.
xe2x80x9cHeteroarylxe2x80x9d is an aromatic ring containing carbon atoms and from 1 to about 6 heteroatoms in the ring. Heteroaryl rings are monocyclic or fused bicyclic ring systems. Monocyclic heteroaryl rings contain from about 5 to about 9 member atoms (carbon and heteroatoms), preferably 5 or 6 member atoms, in the ring. Bicyclic heteroaryl rings contain from 8 to 17 member atoms, preferably 8 to 12 member atoms, in the ring. Bicyclic heteroaryl rings include ring systems wherein one ring is heteroaryl and the other ring is aryl, heteroaryl, cycloalkyl, or heterocycloalkyl. Preferred bicyclic heteroaryl ring systems comprise 5-, 6- or 7-membered rings fused to 5-, 6-, or 7-membered rings. Heteroaryl rings may be unsubstituted or substituted with from 1 to 4 substituents on the ring. Heteroaryl may be substituted with halo, cyano, nitro, hydroxy, carboxy, amino, acylamino, alkyl, heteroalkyl, haloalkyl, phenyl, alkoxy, aryloxy, heteroaryloxy, or any combination thereof. Preferred heteroaryl rings include, but are not limited to, the following: 
xe2x80x9cHeteroaryloxyxe2x80x9d is an oxygen radical having a heteroaryl substituent (i.e., xe2x80x94Oxe2x80x94heteroaryl). Preferred heteroaryloxy groups include (for example) pyridyloxy, furanyloxy, (thiophene)oxy, (oxazole)oxy, (thiazole)oxy, (isoxazole)oxy, pyrmidinyloxy, pyrazinyloxy, and benzothiazolyloxy.
xe2x80x9cHeterocycloalkylxe2x80x9d is a saturated or unsaturated ring containing carbon atoms and from 1 to about 4 (preferably 1 to 3) heteroatoms in the ring. Heterocycloalkyl rings are not aromatic. Heterocycloalkyl rings are monocyclic or bicyclic ring systems. Monocyclic heterocycloalkyl rings contain from about 3 to about 9 member atoms (carbon and heteroatoms), preferably from 5 to 7 member atoms, in the ring. Bicyclic heterocycloalkyl rings contain from 7 to 17 member atoms, preferably 7 to 12 member atoms, in the ring. Bicyclic heterocycloalkyl rings contain from about 7 to about 17 ring atoms, preferably from 7 to 12 ring atoms. Bicyclic heterocycloalkyl rings may be fused, spiro, or bridged ring systems. Preferred bicyclic heterocycloalkyl rings comprise 5-, 6- or 7-membered rings fused to 5-, 6-, or 7-membered rings. Heterocycloalkyl rings may be unsubstituted or substituted with from 1 to 4 substituents on the ring. Heterocycloalkyl may be substituted with halo, cyano, hydroxy, carboxy, keto, thioketo, amino, acylamino, acyl, amido, alkyl, heteroalkyl, haloalkyl, phenyl, alkoxy, aryloxy or any combination thereof. Preferred substituents on heterocycloalkyl include halo and haloalkyl. Preferred heterocycloalkyl rings include, but are not limited to, the following: 
xe2x80x9cHeterocyclic ringxe2x80x9d encompasses both hetercycloalkyl and heteroaryl moieties, as those terms are defined herein.
xe2x80x9cSpirocyclexe2x80x9d is an alkyl or heteroalkyl diradical substituent of alkyl or heteroalkyl wherein said diradical substituent is attached geminally and wherein said diradical substituent forms a ring, said ring containing 4 to 8 member atoms (carbon or heteroatom), preferably 5 or 6 member atoms.
xe2x80x9cLowerxe2x80x9d alkoxy, alkylthio, alkyl, alkene or alkyne moiety (e.g., xe2x80x9clower alkylxe2x80x9d) is a chain comprised of 1 to 6, preferably from 1 to 4, carbon atoms in the case of alkyl, alkoxy and alkylthio, and 2 to 6, preferably 2 to 4, carbon atoms in the case of alkene and alkyne.
While alkyl, heteroalkyl, cycloalkyl, and heterocycloalkyl groups may be substituted with hydroxy, amino, and amido groups as stated above, the following are not envisioned in the invention:
1. Enols (OH attached to an alkene carbon).
2. Amino groups attached to a carbon bearing a double bond (except for vinylogous amides).
3. More than one hydroxy, amino, or amido attached to a single carbon (except where two nitrogen atoms are attached to a single carbon atom and all three atoms are member atoms within a heterocycloalkyl ring).
4. Hydroxy, amino, or amido attached to a carbon that also has a heteroatom attached to it.
5. Hydroxy, amino, or amido attached to a carbon that also has a halogen attached to it.
A xe2x80x9cpharmaceutically-acceptable saltxe2x80x9d is a cationic salt formed at any acidic (e.g., carboxyl) group, or an anionic salt formed at any basic (e.g., amino, alkylamino, dialkylamino, morphylino, and the like) group on the compound of the invention. Since many of the compounds of the invention are zwitterionic, either salt is possible and acceptable. Many such salts are known in the art. Preferred cationic salts include the alkali metal salts (such as sodium and potassium), alkaline earth metal salts (such as magnesium and calcium) and organic salts, such as ammonio. Preferred anionic salts include halides, sulfonates, carboxylates, phosphates, and the like. Clearly contemplated in such salts are addition salts that may provide an optical center, where once there is none. For example, a chiral tartrate salt may be prepared from the compounds of the invention, and this definition includes such chiral salts. Salts contemplated are nontoxic in the amounts administered to the patient-animal, mammal or human.
The compounds of the invention are sufficiently basic to form acid-addition salts. The compounds are useful both in the free-base form and the form of acid-addition salts, and both forms are within the purview of the invention. The acid-addition salts are in some cases a more convenient form for use. In practice, the use of the salt form inherently amounts to the use of the base form of the active. Acids used to prepare acid-addition salts include preferably those which produce, when combined with the free base, medicinally acceptable salts. These salts have anions that are relatively innocuous to the animal organism, such as a mammal, in medicinal doses of the salts so that the beneficial property inherent in the free base are not vitiated by any side effects ascribable to the acid""s anions.
Examples of appropriate acid-addition salts include, but are not limited to hydrochloride, hydrobromide, hydroiodide, sulfate, hydrogensulfate, acetate, trifluoroacetate, nitrate, citrate, fumarate, formate, stearate, succinate, maleate, malonate, adipate, glutarate, lactate, propionate, butyrate, tartrate, methanesulfonate, trifluoromethanesulfonate, p-toluenesulfonate, dodecyl sulfate, cyclohexanesulfamate, and the like. However, other appropriate medicinally acceptable salts within the scope of the invention are those derived from other mineral acids and organic acids. The acid-addition salts of the basic compounds are prepared by several methods. For example, the free base can be dissolved in an aqueous alcohol solution containing the appropriate acid and the salt is isolated by evaporation of the solution. Alternatively, they may be prepared by reacting the free base with an acid in an organic solvent so that the salt separates directly. Where separation of the salt is difficult, it can be precipitated with a second organic solvent, or can be obtained by concentration of the solution.
Although medicinally acceptable salts of the basic compounds are preferred, all acid-addition salts are within the scope of the present invention. All acid-addition salts are useful as sources of the free base form, even if the particular salt per se is desired only as an intermediate product. For example, when the salt is formed only for purposes of purification or identification, or when it is used as an intermediate in preparing a medicinally acceptable salt by ion exchange procedures, these salts are clearly contemplated to be a part of this invention.
Such salts are well understood by the skilled artisan, and the skilled artisan is able to prepare any number of salts given the knowledge in the art. Furthermore, it is recognized that the skilled artisan may prefer one salt over another for reasons of solubility, stability, formulation ease and the like. Determination and optimization of such salts is within the purview of the skilled artisan""s practice.
xe2x80x9cHostxe2x80x9d is a substrate capable of sustaining a microbe, preferably it is a living organism, more preferably an animal, more preferably a mammal, more preferably still a human.
xe2x80x9cBiohydrolyzable amidesxe2x80x9d are aminoacyl, acylamino, or other amides of the compounds of the invention, where the amide does not essentially interfere, preferably does not interfere, with the activity of the compound, or where the amide is readily converted in vivo by a host to yield an active compound.
xe2x80x9cBiohydrolyzable imidesxe2x80x9d are imides of compounds of the invention, where the imide does not essentially interfere, preferably does not interfere, with the activity of the compound, or where the imide is readily converted in vivo by a host to yield an active compound. Preferred imides are hydroxyimides.
xe2x80x9cBiohydrolyzable estersxe2x80x9d are esters of compounds of the invention, where the ester does not essentially interfere, preferably does not interfere, with the antimicrobial activity of the compound, or where the ester is readily converted in a host to yield an active compound. Many such esters are known in the art, as described in U.S. Pat. No. 4,783,443, issued to Johnston and Mobashery on Nov. 8, 1988 (incorporated by reference herein). Such esters include lower alkyl esters, lower acyloxy-alkyl esters (such as acetoxymethyl, acetoxyethyl, aminocarbonyloxymethyl, pivaloyloxymethyl and pivaloyloxyethyl esters), lactonyl esters (such as phthalidyl and thiophthalidyl esters), lower alkoxyacyloxyalkyl esters (such as methoxycarbonyloxymethyl, ethoxycarbonyloxyethyl and isopropoxycarbonyloxyethyl esters), alkoxyalkyl esters, choline esters and alkylacylaminoalkyl esters (such as acetamidomethyl esters).
The illustration of specific protected forms and other derivatives of the Formula 1 compounds is not intended to be limiting. The application of other useful protecting groups, salt forms, etc. is within the ability of the skilled artisan.
A xe2x80x9csolvatexe2x80x9d is a complex formed by the combination of a solute (e.g., a quinolone) and a solvent (e.g., water). See J. Honig et al., The Van Nostrand Chemist""s Dictionary, p. 650 (1953). Pharmaceutically-acceptable solvents used according to this invention include those that do not interfere with the biological activity of the quinolone or quinolone derivative (e.g., water, ethanol, acetic acid, N,N-dimethylformamide and others known or readily determined by the skilled artisan).
The terms xe2x80x9coptical isomerxe2x80x9d, xe2x80x9cstereoisomerxe2x80x9d, and xe2x80x9cdiastereomerxe2x80x9d have the standard art recognized meanings (see, e.g., Hawley""s Condensed Chemical Dictionary, 11th Ed.). The illustration of specific protected forms and other derivatives of the compounds of the instant invention is not intended to be limiting. The application of other useful protecting groups, salt forms, etc. is within the ability of the skilled artisan.
The compounds of the invention may have one or more chiral centers. As a result, one may selectively prepare one optical isomer, including diastereomer and enantiomer, over another, for example by use of chiral starting materials, catalysts or solvents, one may prepare both stereoisomers or both optical isomers, including diastereomers and enantiomers at once (a racemic mixture). Since the compounds of the invention may exist as racemic mixtures, mixtures of optical isomers, including diastereomers and enantiomers, or stereoisomers, they may be separated using known methods, such as chiral resolution, chiral chromatography and the like.
In addition, it is recognized that one optical isomer, including diastereomer and enantiomer, or stereoisomer may have favorable properties over the other. Thus when disclosing and claiming the invention, when one racemic mixture is disclosed, it is clearly contemplated that both optical isomers, including diastereomers and enantiomers, or stereoisomers substantially free of the other are disclosed and claimed as well.
As used herein, a quinolone derivative includes prodrugs of a quinolone, or an active drug made from a quinolone. Preferably, such derivatives include lactams (e.g., cephems, carbacephems, penems, monolactams, etc.) covalently linked to the quinolone optionally via a spacer. Such derivatives and methods to make and use them are apparent to the skilled artisan, given the teachings of this specification.
II. Compounds:
The subject invention involves compounds of Formula (I): 
wherein A1, X, Y, a, b, R2, R3, R5, R6, R7, R8, R9, R9xe2x80x2 and R10 are as defined in the Summary of the Invention section above.
With reference to Formula (I), the description above indicates that in one embodiment (defined in sub-part (A)), the nucleus of the compounds will include only two fused rings as depicted. Alternatively, the nucleus of the compounds will include three or four fused rings, as defined in sub-parts (B) through (D). These alternative embodiments are depicted as Formula (B), Formula (C) and Formula (D), respectively, below.
With respect to each of the preferred embodiments described, a non-limiting list of preferred compounds is also set forth in tabular form. It will be recognized that for purification, administration and the like, salts and other derivatives of the above compounds are often used. Thus, a pharmaceutically-acceptable salt, hydrate, or biohydrolyzable ester, amide or imide thereof is contemplated as part of the subject invention and is meant to be included in the tables.
Table I contains a non-limiting list of preferred compounds of Formula (I) where X is a carbon atom, a represents a double bond, b represents a single bond, Y is N(R1), each R10 is hydrogen and no additional fused rings are formed (i.e., compounds of sub-part (A)).
Table Ia contains a non-limiting list of preferred compounds of Formula (Ia). 
These compounds are those of Formula (I) where X is a nitrogen atom, a represents a single bond, b represents a double bond, Y is C(R1), each R10 is hydrogen and no additional fused rings are formed.
With regard to Formula (B), the compounds have a structure according to the following structure: 
where R1 and R8 of Formula (I) join to form a 6-membered heterocycloalkyl, and where D is substituted or unsubstituted xe2x80x94Cxe2x80x94 or xe2x80x94Nxe2x80x94 or D is xe2x80x94Oxe2x80x94or S; R13 and R13xe2x80x2 are independently selected from hydrogen and lower alkyl; and E is selected from xe2x80x94Oxe2x80x94, xe2x80x94Sxe2x80x94, substituted or unsubstituted xe2x80x94Cxe2x80x94 and substituted or unsubstituted xe2x80x94Nxe2x80x94. Preferred for D is xe2x80x94Oxe2x80x94. Preferred for E is xe2x80x94CH2xe2x80x94. Preferred is where R13 is hydrogen and R13 is lower alkyl, preferably methyl.
Table B contains a non-limiting list of preferred compounds of Formula (B).
(Stereochemistry at the carbon atom bearing R13 and R13xe2x80x2 is preferably the S-configuration)
With regard to Formula (C), the compounds have a structure according to the following: 
where R1 and R2 of Formula (I) join to form ring L, which is a mono- or bicyclic heterocycle comprising Nxe2x80x2.
Table C-1 contains a non-limiting list of preferred compounds of Formula (C) having the following formula:
Table C-2 contains a non-limiting list of preferred compounds of Formula (C) having the following formula:
With regard to Formula (D), the compounds have a structure according to the following structure: 
where R2 and R3 of Formula (I) join to form a 5-membered heterocycloalkyl, where T is selected from xe2x80x94Oxe2x80x94, xe2x80x94Sxe2x80x94and substituted or unsubstituted xe2x80x94Nxe2x80x94. Preferred T is xe2x80x94Sxe2x80x94.
Table D contains a non-limiting list of preferred compounds of Formula (D).
More preferred compounds of the present invention are those where R8 and R1 join to form a ring (compounds of Formula (B)) and those where none of R8, R1, R2 or R3 join to form a ring. Particularly preferred are those where none of R8, R1, R2 or R3 join to form a ring.
The following provides a description of particularly preferred moieties with respect to each of Formulas (I), (Ia), (B), (C) and (D), but is not intended to limit the scope of the claims.
A1 is selected from xe2x80x94Nxe2x80x94 and xe2x80x94C(R8)xe2x80x94. Preferred is where A1 is xe2x80x94C(R8)xe2x80x94, where R5 is selected from hydrogen, halo, lower alkoxy, lower alkylthio, lower alkyl and lower alkenyl. When R8 is lower alkyl, preferred is where R8 has from 1 to about 2 carbon atoms; methyl is preferred. When R8 is lower alkene, preferred R8 will have from 2 to about 4 carbon atoms; ethenyl is preferred. When R8 is lower alkoxy, preferred R8 has from 1 to about 4 carbon atoms. When R8 is lower alkylthio, preferred R8 has from 1 to about 4 carbon atoms. All R8 alkyl and alkene moieties are unsubstituted or substituted with fluoro. Preferred R8 is selected from chloro, methyl, methoxy, methylthio, monofluoromethyl, difluoromethyl, trifluoromethyl, monofluoromethoxy, difluoromethoxy, and trifluoromethoxy. More preferred R8 is selected from methyl substituted with from 1 to 3 fluoro, methoxy, methylthio, and chloro; especially either methoxy, methylthio or chloro.
X is selected from xe2x80x94Cxe2x80x94 and xe2x80x94Nxe2x80x94. When X is xe2x80x94Cxe2x80x94, a is a double bond and b is a single bond. In contrast, when X is xe2x80x94Nxe2x80x94, a is a single bond and b is a double bond.
Y is selected from xe2x80x94N(R1)xe2x80x94 and xe2x80x94C(R1)xe2x80x94. However, Y is N(R1) only if X is xe2x80x94Cxe2x80x94 and Y is xe2x80x94C(R1)xe2x80x94 only if X is xe2x80x94Nxe2x80x94.
R1 is selected from C3 to about C6 cycloalkyl, C4 to about C6 heterocycloalkyl, lower alkyl, lower alkene, a 6-membered aryl and a 6-membered heteroaryl. Preferred is where R1 is C3 to about C6 cycloalkyl, C3 to about C6 heterocycloalkyl, lower alkyl or lower alkene. Most preferred is C3 to about C6 cycloalkyl and lower alkyl. When R1 is cycloalkyl, preferred are rings having from about 3 to about 5 ring carbon atoms, more preferably 3 ring carbon atoms. R1 cycloalkyl moieties are preferably saturated or unsaturated with one double bond; more preferably R1 cycloalkyl is saturated. When R1 is linear lower alkyl, preferred is where R1 contains from 1 to about 2 carbon atoms; methyl and ethyl are preferred, most preferred is ethyl. When R1 is lower linear alkene, preferred is where R1 contains from 2 to about 3 carbon atoms; ethenyl is preferred. When R1 is branched lower alkyl or lower alkene, preferred is where R1 contains from 3 to about 4 carbon atoms; branched lower alkyl is preferred; t-butyl is particularly preferred. All of the R1 moieties mentioned in this paragraph are unsubstituted or substituted. When R1 is substituted, preferred is one or more fluorine atoms. When R1 is a 6-membered aryl or a 6-membered heteroaryl aryl, the ring is unsubstituted or substituted with from 1 to about 3 fluorine atoms, one amino group (preferably at the 3-position of the ring), one hydroxy (preferably in the 4-position of the ring), or a combination of these substituents; substituted phenyl are preferred. Most preferred R1 moieties are selected from cyclopropyl, ethyl, phenyl substituted with 1 to 3 fluoro, and 4-hydroxyphenyl; more preferred is 2,4-difluorophenyl, and especially cyclopropyl or ethyl.
R2 is hydrogen.
R3 is selected from hydrogen and hydroxy. Preferred is hydroxy. When R3 is hydroxy, it and the carbonyl to which it is attached form a carboxylic acid moiety. As such, it is a potential point of formation for the subject compounds of pharmaceutically-acceptable salts, and biohydrolizable esters, aminoacyls, and amides, as described herein. Compounds having any such variations at the R3 position are included in the subject invention.
R5 is selected from hydrogen, hydroxy, amino, halo, lower alkyl, lower alkene and lower alkoxy. When R5 is lower alkyl, preferred is where R5 has 1 to about 2 carbon atoms, preferably 1 carbon atom. When R5 is lower alkene, preferred is where R5 has 2 carbon atoms. When R5 is lower alkoxy, preferred is where R5 has from 1 to 2 carbon atoms. When R5 is amino, preferred is xe2x80x94NH2. All R5 alkyl, alkene and lower alkoxy moieties are unsubstituted or substituted with fluoro moieties. Preferred R5 is selected from hydrogen, hydroxy, chloro, bromo, amino, methyl, monofluoromethyl, difluoromethyl and trifluoromethyl. More preferred R5 is selected from hydrogen, hydroxy, amino, and methyl; most preferred is hydrogen.
R6 is selected from fluoro and chloro. Preferred is fluoro.
R is xe2x80x94Qxe2x80x94C(R11)(R11xe2x80x2)(R11xe2x80x3), where Q is selected from xe2x80x94Sxe2x80x94, xe2x80x94Oxe2x80x94and xe2x80x94C(R12)(R12xe2x80x2)xe2x80x94, where R12 and R12xe2x80x2 are each independently selected from hydrogen and fluoro; where R11, R11xe2x80x2 and R11xe2x80x3 are each independently selected from hydrogen, hydroxy and halo. Alternatively, that R11 and R12 can both be nil, such that a double bond is formed between the respective carbon atoms. More preferred is where each of R11, R11xe2x80x2 and R11xe2x80x3 is hydrogen. Also preferred is where R7 is methoxy, thiomethoxy or ethyl. Most preferred is where R7 is ethyl.
R9 and R9xe2x80x2 are each independently selected from hydrogen and alkyl (preferably lower alkyl), or R9 and R9xe2x80x2 join to form a heterocyclic ring containing the nitrogen atom to which they are bonded. Preferred is where R9 and R9xe2x80x2 are independently selected from hydrogen and methyl. Most preferred is where both R9 and R9xe2x80x2 are hydrogen.
R10 represents the moieties on the piperidine ring other than the depicted R7 and xe2x80x94NR9R9xe2x80x2 moieties, where each R10 is independently selected from hydrogen, lower alkyl and fluoro.
As used herein, any radical is independently selected each time it is used (e.g., R1 and R5 need not be the same in all occurrences in defining a given compound of this invention).
The compounds of the invention may contain chiral center(s), thus any such compound includes and contemplates each optical isomer, diastereomer or enantiomer thereof, in purified or substantially purified form, and mixtures thereof, including racemic mixtures.
The following exemplary compounds are made using the procedures described herein and variations thereof which are within the purview of the skilled artisan""s practice. The examples below do not limit the invention, but rather serve to illustrate some of the embodiments of the invention.
In one aspect, the present invention is directed to compounds of Formula (I) wherein X is xe2x80x94Cxe2x80x94, Y is xe2x80x94N(R1)xe2x80x94, a is a double bond and b is a single bond. In this aspect, preferred are compounds having a structure according to the following Formula (II): 
where A1, R1, R5, R6 and R7 are as defined with regard to Formula (I). In a particularly preferred embodiment, the compounds are those of Formula (II) where A1 is xe2x80x94C(R8)xe2x80x94. Most preferred compounds of Formula (II) are those where R8 and R1 do not join to form a ring. With respect to Formula (II), most preferred is where R7 is ethyl and R6 is fluoro.
In another aspect, the present invention is directed to compounds of Formula (I) where X is xe2x80x94Nxe2x80x94, Y is xe2x80x94C(R1)xe2x80x94, a is a single bond and b is a double bond. In this aspect, preferred are compounds having a structure according to the following Formula (III): 
where R1, R5, R6, R7 and R8 are as defined with regard to Formula (I). Preferred compounds of Formula (III) are those where R8 and R1 do not join to form a ring. Most preferred is where R7 is ethyl and R6 is fluoro.
The subject invention compounds above are also useful precursors for compounds of formula Q-L-B, wherein Q is a compound of Formula 1, L is a linking moiety, and B is a lactam-containing moiety. This formula includes optical isomers, disatereomers or enantiomers thereof; pharmaceutically-acceptable salts, hydrates, or biohydrolyzable esters, amides and imides thereof. These compounds and their uses are disclosed in U.S. Pat. No. 5,180,719 issued Jan. 19, 1993; U.S. Pat. No. 5,387,748 issued Feb. 7, 1995; U.S. Pat. No. 5,491,139 issued Feb. 13, 1996; U.S. Pat. No. 5,530,116 issued Jun. 25, 1996; and European Patent Publication Nos. 366,189, published May 2, 1990, and 366,640 published May 2, 1990, all incorporated herein by reference. For compositions and methods of use, the compounds of formula Q-L-B are useful in the same way as compounds of Formula 1. Thus, they can be interchanged in the composition examples herein.
Biological activities of the invention compounds can be compared to ciprofloxacin and the other known antimicrobial quinolone compounds. Compounds of the subject invention provide better antibacterial properties against certain quinolone resistant bacteria compared to ciprofloxacin and certain other prior art compounds. When tested against quinolone-resistant bacteria such as S. aureus, S. saprophyticus, E. faecalis, S. pyogenes, S. pneumoniae, S. viridans, E. coli, P. aeruginosa, P. mirabilis, K pneumoniae, E. cloacae, certain compounds of the subject invention have been found to have MIC values (1 xcexcg/mL) that are up to about 500 times lower than ciprofloxacin.
III. General Reaction Schemes for Compound Preparation:
In making the compounds of the invention, the order of synthetic steps may be varied to increase yield of desired product. In addition, the skilled artisan will also recognize the judicious choice of reactants, solvents, and temperatures is an important component in successful synthesis. While the determination of optimal conditions, etc. is routine, it will be understood that a variety of compounds can be generated in a similar fashion, using the guidance of the scheme below. Specific synthetic examples are set forth for a variety of compounds in Section VII.
The starting materials used in preparing the compounds of the invention are known, made by known methods, or are commercially available as a starting material.
It is recognized that the skilled artisan in the art of organic chemistry can readily carry out standard manipulations of organic compounds without further direction; that is, it is well within the scope and practice of the skilled artisan to carry out such manipulations. These include, but are not limited to, reduction of carbonyl compounds to their corresponding alcohols, oxidations, acylations, aromatic substitutions, both electrophilic and nucleophilic, etherifications, esterification and saponification and the like. Examples of these manipulations are discussed in standard texts such as March, Advanced Organic Chemistry (Wiley), Carey and Sundberg, Advanced Organic Chemistry (Vol. 2), Fieser and Feiser, Reagents for Organic Synthesis (16 volumes), L. Paquette, Encyclopedia of Reagents for Organic Synthesis (8 volumes), Frost and Fleming, Comprehensive Organic Synthesis (9 volumes) and the like.
The skilled artisan will readily appreciate that certain reactions are best carried out when other functionality is masked or protected in the molecule, thus avoiding any undesirable side reactions and/or increasing the yield of the reaction. Often the skilled artisan utilizes protecting groups to accomplish such increased yields or to avoid the undesired reactions. These reactions are found in the literature and are also well within the scope of the skilled artisan. Examples of many of these manipulations can be found for example in T. Greene, Protecting Groups in Organic Synthesis. Of course, amino acids used as starting materials with reactive side chains are preferably blocked to prevent undesired side reactions.
General procedures for preparing quinolone moieties useful in making the compounds of the subject invention are described in the following references, all incorporated by reference herein (including articles listed within these references): Progress in Drug Research, Vol. 21, pp. 9-104 (1977); J. Med. Chem., Vol. 23, pp. 1358-1363 (1980); J. Med. Chem., Vol. 29, pp. 2363-2369 (1986); J. Med. Chem., Vol. 31, p. 503 (1988); J. Med. Chem., Vol. 31, pp. 503-506 (1988); J. Med. Chem., Vol. 31, pp. 983-991 (1988); J. Med. Chem., Vol. 31, pp. 991-1001 (1988); J. Med. Chem., Vol. 31, pp. 1586-1590 (1988); J. Med. Chem., Vol. 31, pp. 1598-1611 (1988); J. Med. Chem., Vol. 32, pp. 537-542 (1989); J. Med. Chem., Vol. 32, p. 1313 (1989); J. Med. Chem., Vol. 32, pp. 1313-1318 (1989); Drugs Exptl. Clin. Res., Vol. 14, pp. 379-383 (1988); J. Pharm. Sci., Vol. 78, pp. 585-588 (1989); J. Het. Chem., Vol. 24, pp. 181-185 (1987); J. Het. Chem., Vol. 25, pp. 479-485 (1988); Chem. Pharm. Bull., Vol. 35, pp. 2281-2285 (1987); Chem. Pharm. Bull., Vol. 36, pp. 1223-1228 (1988); U.S. Pat. No. 4,594,347, Jun. 10, 1986; U.S. Pat. No. 4,599,334, Jul. 8, 1986; U.S. Pat. No. 4,687,770, Aug. 1, 1987; U.S. Pat. No. 4,689,325, Aug. 25, 1987; U.S. Pat. No. 4,767,762, Aug. 30, 1988; U.S. Pat. No. 4,771,055, Sep. 13, 1988; U.S. Pat. No. 4,795,751, Jan. 3, 1989; U.S. Pat. No. 4,822,801, Apr. 18, 1989; U.S. Pat. No. 4,839,355, Jun. 13, 1989; U.S. Pat. No. 4,851,418, Jul. 25, 1989; U.S. Pat. No. 4,886,810, Dec. 12, 1989; U.S. Pat. No. 4,920,120, Apr. 24, 1990; U.S. Pat. No. 4,923,879, May 8, 1990; U.S. Pat. No. 4,954,507, Sep. 4, 1990; U.S. Pat. No. 4,956,465, Sep. 11, 1990; U.S. Pat. No. 4,977,154, Dec. 11, 1990; U.S. Pat. No. 4,980,470, Dec. 25, 1990; U.S. Pat. No. 5,013,841, May 7, 1991; U.S. Pat. No. 5,045,549, Sep. 3, 1991; U.S. Pat. No. 5,290,934, Mar. 1, 1994; U.S. Pat. No. 5,328,908, Jul. 12, 1994; U.S. Pat. No. 5,430,152, Jul. 4, 1995; European Patent Publication 172,651, Feb. 26, 1986; European Patent Publication 230,053, Jul. 29, 1987; European Patent Publication 230,946, Aug. 5, 1987; European Patent Publication 247,464, Dec. 2, 1987; European Patent Publication 284,935, Oct. 5, 1988; European Patent Publication 309,789, Apr. 5, 1989; European Patent Publication 332,033, Sep. 13, 1989; European Patent Publication 342,649, Nov. 23, 1989; and Japanese Patent Publication 09/67,304 (1997).
The quinolone compounds of the subject invention may be prepared in several ways. Versatile methodologies for providing the compounds of the invention are shown in Scheme I below: 
Methodologies for providing the compounds of the invention where X is xe2x80x94Nxe2x80x94 and Y is xe2x80x94C(R1)xe2x80x94 are shown in Scheme II below: 
IV. Compositions:
The compositions of this invention comprise:
(a) a safe and effective amount of the compound of the invention
(b) a pharmaceutically-acceptable excipient.
The compositions may also optionally comprise other antimicrobials or other actives, which may or may not act synergistically with the invention.
A xe2x80x9csafe and effective amountxe2x80x9d of a quinolone is an amount that is effective, to inhibit microbial growth at the site of an infection to be treated in a host, without undue adverse side effects (such as toxicity, irritation, or allergic response), commensurate with a reasonable benefit/risk ratio when used in the manner of this invention. The specific xe2x80x9csafe and effective amountxe2x80x9d will vary with such factors as the particular condition being treated, the physical condition of the patient, the duration of treatment, the nature of concurrent therapy (if any), the specific dosage form to be used, the excipient employed, the solubility of the quinolone therein, and the dosage regimen desired for the composition.
The compositions of this invention are preferably provided in unit dosage form. As used herein, a xe2x80x9cunit dosage formxe2x80x9d is a composition of this invention containing an amount of a quinolone that is suitable for administration to a human or lower animal subject, in a single dose, according to good medical practice. These compositions preferably contain from about 30 mg, more preferably from about 50 mg, more preferably still from about 100 mg, preferably to about 20,000 mg, more preferably to about 7,000 mg, more preferably still to about 1,000 mg, most preferably to about 500 mg, of a quinolone.
The compositions of this invention may be in any of a variety of forms, suitable (for example) for oral, rectal, topical or parenteral administration. Depending upon the particular route of administration desired, a variety of pharmaceutically-acceptable excipients well-known in the art may be used. These include solid or liquid fillers, diluents, hydrotropes, surface-active agents, and encapsulating substances. Optional pharmaceutically-active materials may be included, which do not substantially interfere with the antimicrobial activity of the quinolone. The amount of excipient employed in conjunction with the quinolone is sufficient to provide a practical quantity of material for administration per unit dose of the quinolone. Techniques and compositions for making dosage forms useful in the methods of this invention are described in the following references, all incorporated by reference herein: Modern Pharmaceutics, Vol. 7, Chapters 9 and 10 (Banker and Rhodes, editors, 1979); Lieberman et al., Pharmaceutical Dosage Forms: Tablets (1981); and Ansel, Introduction to Pharmaceutical Dosage Forms 2d Edition (1976).
In particular, pharmaceutically-acceptable excipients for systemic administration include sugars, starches, cellulose and its derivatives, malt, gelatin, talc, calcium sulfate, vegetable oils, synthetic oils, polyols, alginic acid, phosphate buffer solutions, emulsifiers, isotonic saline, and pyrogen-free water. Preferred excipients for parenteral administration include propylene glycol, ethyl oleate, pyrrolidone, ethanol, and sesame oil. Preferably, the pharmaceutically-acceptable excipient, in compositions for parenteral administration, comprises at least about 90% by weight by the total composition.
In addition, dosages for injection may be prepared in dried or lyophilized form. Such forms can be reconstituted with water or saline solution, depending on the preparation of the dosage form. Such forms may be packaged as individual dosages or multiple dosages for easier handling. Where lyophilized or dried dosages are used, the reconstituted dosage form is preferably isotonic, and at a physiologically compatible pH.
Various oral dosage forms can be used, including such solid forms as tablets, capsules, granules and bulk powders. These oral forms comprise a safe and effective amount, usually at least about 5%, and preferably from about 25% to about 50%, of the quinolone. Tablets can be compressed, tablet triturates, enteric-coated, sugar-coated, film-coated, or multiple-compressed, containing suitable binders, lubricants, diluents, disintegrating agents, coloring agents, flavoring agents, flow-inducing agents, and melting agents. Liquid oral dosage forms include aqueous solutions, emulsions, suspensions, solutions and/or suspensions reconstituted from non-effervescent granules, and effervescent preparations reconstituted from effervescent granules, containing suitable solvents, preservatives, emulsifying agents, suspending agents, diluents, sweeteners, melting agents, coloring agents and flavoring agents, such are well known to the skilled artisan. Preferred excipients for oral administration include gelatin, propylene glycol, cottonseed oil and sesame oil.
The compositions of this invention can also be administered topically to a subject, i.e., by the direct laying on or spreading of the composition on the epidermal or epithelial tissue of the subject. Such compositions include, for example, lotions, creams, solutions, gels and solids. These topical compositions preferably comprise a safe and effective amount, usually at least about 0.1%, and preferably from about 1% to about 5%, of the quinolone. Suitable excipients for topical administration preferably remain in place on the skin as a continuous film, and resist being removed by perspiration or immersion in water. Generally, the excipient is organic in nature and capable of having dispersed or dissolved therein the quinolone. The excipient may include pharmaceutically-acceptable emolients, emulsifiers, thickening agents, and solvents and the like; these are well known to the skilled artisan.
V. Methods of Using the Compounds:
This invention also provides methods of treating an infectious disorder in a human or other animal subject, by administering a safe and effective amount of a quinolone to said subject. As used herein, an xe2x80x9cinfectious disorderxe2x80x9d is any disorder characterized by the presence of a microbial infection. Preferred methods of this invention are for the treatment of bacterial infections. Such infectious disorders include (for example) central nervous system infections, external ear infections, infections of the middle ear (such as acute otitis media), infections of the cranial sinuses, eye infections, infections of the oral cavity (such as infections of the teeth, gums and mucosa), upper respiratory tract infections, lower respiratory tract infections, including pneumonia, genitourinary infections, gastrointestinal infections, gynecological infections, septicemia, sepsis, peritonitis, bone and joint infections, skin and skin structure infections, bacterial endocarditis, bums, antibacterial prophylaxis of surgery, and antibacterial prophylaxis in post-operative patients or in immunosuppressed patients (such as patients receiving cancer chemotherapy, or organ transplant patients).
The term xe2x80x9ctreatmentxe2x80x9d is used herein to mean that, at a minimum, administration of a compound of the present invention mitigates a disease associated an infectious disorder in a host, preferably in a mammalian subject, more preferably in humans. Thus, the term xe2x80x9ctreatmentxe2x80x9d includes: preventing an infectious disorder from occurring in a host, particularly when the host is predisposed to acquiring the disease, but has not yet been diagnosed with the disease; inhibiting the infectious disorder; and/or alleviating or reversing the infectious disorder. Insofar as the methods of the present invention are directed to preventing infectious disorders, it is understood that the term xe2x80x9cpreventxe2x80x9d does not require that the disease state be completely thwarted. (See Webster""s Ninth Collegiate Dictionary.) Rather, as used herein, the term preventing refers to the ability of the skilled artisan to identify a population that is susceptible to infectious disorders, such that administration of the compounds of the present invention may occur prior to onset of infection. The term does not imply that the disease state be completely avoided.
The quinolone derivatives and compositions of this invention can be administered topically or systemically. Systemic application includes any method of introducing the quinolone into the tissues of the body, e.g., intrathecal, epidural, intramuscular, transdermal, intravenous, intraperitoneal, subcutaneous, sublingual, rectal, and oral administration. The specific dosage of antimicrobial to be administered, as well as the duration of treatment, are mutually dependent. The dosage and treatment regimen will also depend upon such factors as the specific quinolone used, the resistance pattern of the infecting organism to the quinolone used, the ability of the quinolone to reach minimum inhibitory concentrations at the site of the infection, the nature and extent of other infections (if any), the personal attributes of the subject (such as weight), compliance with the treatment regimen, the age and health status of the patient, and the presence and severity of any side effects of the treatment.
Typically, for a human adult (weighing approximately 70 kilograms), from about 75 mg, more preferably from about 200 mg, most preferably from about 500 mg to about 30,000 mg, more preferably to about 10,000 mg, most preferably to about 3,500 mg, of quinolone is administered per day. Treatment regimens preferably extend from about 1, preferably from about 3 to about 56 days, preferably to about 20 days, in duration. Prophylactic regimens (such as avoidance of opportunistic infections in immunocompromised patients) may extend 6 months, or longer, according to good medical practice.
A preferred method of parenteral administration is through intravenous injection. As is known and practiced in the art, all formulations for parenteral administration must be sterile. For mammals, especially humans, (assuming an approximate body weight of 70 kilograms) individual doses of from about 100 mg, preferably from about 500 mg to about 7,000 mg, more preferably to about 3,500 mg, is acceptable.
In some cases, such as generalized, systemic infections or in immune-compromised patients, the invention may be dosed intravenously. The dosage form is generally isotonic and at physiological pH. The dosage amount will depend on the patient and severity of condition, as well as other commonly considered parameters. Determination of such doses is well within the scope of practice for the skilled practitioner using the guidance given in the specification.
A preferred method of systemic administration is oral administration. Individual doses of from about 20 mg, more preferably from about 100 mg to about 2,500 mg, more preferably to about 500 mg.
Topical administration can be used to deliver the quinolone systemically, or to treat a local infection. The amounts of quinolone to be topically administered depends upon such factors as skin sensitivity, type and location of the tissue to be treated, the composition and excipient (if any) to be administered, the particular quinolone to be administered, as well as the particular disorder to be treated and the extent to which systemic (as distinguished from local) effects are desired.
VI. Examplesxe2x80x94Compound Preparation
a. Precursor Preparationxe2x80x94Nuclei:

3-Methoxy-2,4,5-difluorobenzoic acid (43.9 g) is suspended in dichloromethane (30 mL) and oxalyl chloride (25 mL) is added followed by 4 drops of dry dimethyl formamide (DMF). The mixture is stirred at room temperature for 6 hours and the solvent is removed by evaporation to afford the desired product.
Monoethyl malonate (26.4 g) is dissolved in tetrahydrofuran (THF) (700 mL). The solution is cooled at xe2x88x9250xc2x0 C. and n-butyllithium (160 mL 2.5 M) is added, keeping the temperature belowxe2x88x9250xc2x0 C. The temperature is initially raised to 0xc2x0 C. and cooled back to xe2x88x9250xc2x0 C. 3-methoxy-2,4,5-trifluorobenzoyl chloride (20.6 g) is added, keeping the temperature at xe2x88x9250xc2x0 C., then the reaction mixture is warmed to room temperature. Hydrochloric acid is added until the pH becomes acidic. The organic phase is washed with sodium bicarbonate and dried; evaporation of the solvent affords the desired product.
To a mixture of acetic anhydride (50 mL) and triethyl orthoformate (50 mL) is added ethyl 2,4,5-trifluoro-3-methoxy-benzoyl acetate (52.94 g). The mixture is refluxed for 2 hours, then is cooled to room temperature. The excess reagent is removed by evaporation to provide a thick oil which is dissolved in ethanol (150 mL). Cyclopropylamine (17.2 g) is then added while keeping the temperature at about 20xc2x0 C. The desired product is isolated by filtration and air dried.
Ethyl 3-cyclopropylamino-2-(2,4,5-trifluoro-3-methoxy-benzoyl) acrylate (30.3 g) is dissolved in THF. 60% sodium hydride in oil (4.1 g) is added portion-wise keeping the temperature below 40xc2x0 C. The solution is stirred at room temperature for 2 hours, then poured into water. The desired product is isolated by filtration and air dried.
Ethyl-1-cyclopropyl-1,4-dihydro-6,7-difluoro-8-methoxy-4-oxo-quinoline-3-carboxylate (28.6 g) is suspended in a mixture of acetic acid, water, sulfuric acid (8/6/1, 30 mL) and is refluxed for 2 hours. The reaction mixture is cooled at 0xc2x0 C. and the desired product is collected by filtration.

2,6-dichloro-5-fluoro-3-nicotinic acid (4 g) is suspended in CH2Cl2 and oxalyl chloride (2.72 g) is added followed by 3 drops of DMF. The mixture is allowed to stir for 3 hours at room temperature and the solvent is evaporated to afford the desired product.
Magnesium turnings (0.44 g) are added to a mixture of ethanol (1.5 mL) and carbon tetrachloride (0.15 mL) and diethyl malonate (2.76 mL) is added over 15 minutes. The temperature is maintained at 50xc2x0 C. for 2 hours and then cooled at 0xc2x0 C. 2,6-dichloro-5-fluoro-3-nicotinoyl chloride (4.3 g) is progressively added keeping the temperature below 5xc2x0 C. After one hour at room temperature, the mixture is acidified, diluted with water and extracted with toluene. Evaporation of the solvent affords the desired product.
Ethyl-3-(2,6-dichloro-5-fluoropyridinyl)-3-oxo-2-carboxyethyl propanoate (6 g) is mixed with water (30 mL) and p-toluene sulfonic acid (0.15 g) and heated at 100xc2x0 C. for one hour. After cooling at room temperature the desired product is extracted with ethyl acetate and the desired product is obtained by evaporation of the solvents.
Ethyl-3-(2,6-dichloro-5-fluoropyridinyl)-3-oxo-propanoate (5 g) is mixed with triethyl orthofomate (4.3 mL) and acetic anhydride (4.1 mL) and is refluxed for 2 hours. The mixture is then concentrated under vacuum to afford the desired product.
Ethyl-3-(2,6-dichloro-5-fluoropyridinyl)-3-oxo-2-ethoxymethylene-propanoate (2.65 g) is dissolved in ethanol (5 mL) and the solution is cooled at 0xc2x0 C. Cyclopropylamine (0.8 mL) is added progressively and the mixture is allowed to stir at room temperature for one hour. The desired product is obtained after evaporation of the solvent.
Ethyl-3-(2,6-dichloro-5-fluoropyridinyl)-3-oxo-2-cyclopropylaminomethylene-propanoate (1.09 g) is dissolved in acetonitrile (15 mL) and potassium carbonate (840 mg) is added. The mixture is refluxed for 18 hours and poured on water. The precipitate is filtered and purified by chromatography using dichloromethane 98/methanol 2.

Ethyl hydrogen malonate (26.4 g) is dissolved in THF (700 mL) and the solution is cooled at xe2x88x9235xc2x0 C. 2.5 M nBuLi (160 mL) is added dropwise and the solution is cooled at xe2x88x9258xc2x0 C. A solution of 2,3,4,5-tetrafluorobenzoyl chloride (21.1 g) in THF (10 mL) is added and then the reaction is allowed to warm at room temperature. The solution is poured in 1N HCl and extracted with ether. The extracts are washed with a bicarbonate solution, brine and dried over Sodium sulfate. The desired product is obtained after chromatography with hexane 85, ethyl acetate 15 (24.8 g).
Ethyl-3-(2,3,4,5-tetrafluorophenyl)-3-oxo-propanoate (10 g) is dissolved in a mixture of triethyl orthoformate (10 mL) and acetic anhydride (10 mL) and the solution is refluxed for 3 hours. After concentration under vacuum, the residue is dissolved in dichloromethane and cooled at 0 C. (S)-2-aminopropanol (4.26 g) is added dropwise and the solution is allowed to warm at room temperature. The product is obtained after chromatography using hexane 75, ethyl acetate 25.
Ethyl-3-(2,3,4,5-tetrafluorophenyl)-3-oxo-2-[(2,S)3-amino-2-methyl-propanol-3-yl]-methylene-propanoate (9.78 g) is dissolved in DMF (25 mL) and sodium hydride (1.17 g) is added. After 20 minutes at room temperature, the solution is heated overnight. The solvent is removed under vacuum and the residue is treated with water. The desired product is obtained by filtration.
(3S) ethyl-9,10-difluoro-2,3-dihydro-3-methyl-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate (8.2 g) is dissolved in THF and 10% aqueous KOH (25 mL) is added. The solution is heated to 65xc2x0 C. for 2 hours. The THF is evaporated and the pH is adjusted to 3 by addition of acetic acid. The desired product is obtained by filtration.

N-Cyclopropyl isothiocyanate (5 g) and thiophenol (5.2 mL) are mixed together at 0xc2x0 C. After stirring 30 minutes at 0xc2x0 C., two drops of triethylamine are added to initiate the reaction. The mixture immediately becomes yellow and slowly solidified. The white solid is broken apart and filtered, washing with hexanes to provide the desired product.
Phosphorus pentachloride (10.5 g) is added to Phenyl N-cyclopropyliminomercaptothioformate, the flask is equipped with a reflux condenser, and the solid mixture is heated to 65xc2x0 C. under argon. The solids slowly melted to become a yellow solution. The mixture is allowed to stir 6 hr at 65xc2x0 C., then is cooled to room temperature. The flask is equipped with a distillation apparatus and the desired product is distilled.
Ethyl hydrogen malonate (33.69 g) is dissolved in dry THF (640 mL). The mixture is cooled to xe2x88x9278xc2x0 C. and n-butyllithium (319 mL, 1.6 M) is added at a rapid drop rate such that the internal temperature remains below xe2x88x9230xc2x0 C. The cooling bath is then removed and the mixture is allowed to warm to xe2x88x9220xc2x0 C. The reaction is re-cooled to xe2x88x9278xc2x0 C. and 2,3,4,5,6-pentafluorobenzoyl chloride (25 g) is added in dry THF (40 mL) via cannula. The yellow solution is allowed to warm to room temperature and stir overnight. The reaction mixture is poured into a vigorously stirring solution of diluted HCl (125 mL) and allowed to stir 1 hr, before the layers are separated and the aqueous layer is extracted with ether. The organic phase is washed with saturated aqueous sodium bicarbonate solution and brine and dried over MgSO4. After concentrating, the desired product is distilled at 5 mm Hg.
2,3,4,5,6-Pentafluorobenzoylacetate (6.02 g) is dissolved in dry toluene (100 mL). Dry sodium hydride (0.562 g) is added under argon and the mixture is allowed to stir 30 minutes. Phenyl N-cyclopropyliminochlorothioformate (6.78 g) is then added in dry toluene (15 mL). The resulting mixture is heated to 50xc2x0 C. for 4 hr, then to reflux for 20 hr before being cooled to room temperature and diluted with dichloromethane. The organic layer is washed once with water, dried over MgSO4, and concentrated to give a dark oil which is applied to a column of silica gel with 15% acetone in hexanes.
Ethyl 1-cyclopropyl-2-phenylthio-5,6,7,8-tetrafluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (3.38 g) is dissolved in dichloromethane (100 mL). m-Chloroperbenzoic acid (1.9 g) is added and the solution is allowed to stir at room temperature overnight. The reaction mixture is extracted with sodium bicarbonate, dried over MgSO4 and concentrated under vacuum. The desired product is obtained after purification by chromatography, using 15% acetone in hexanes.
Ethyl 1-cyclopropyl-2-phenylsulfinyl-5,6,7,8-tetrafluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (0.225 g) is dissolved in THF (15 mL) and the solution is cooled at 0xc2x0 C. Sodium hydrosulfite (60 mg) dissolved in water (2 mL) is then added followed by a solution of sodium bicarbonate (0.5 g in 10 mL). The solution is stirred at 0xc2x0 C. for one hour and hydroxylaminexe2x80x94Oxe2x80x94sulfonic acid (0.264 g) is added. The solution is allowed to warm at room temperature and after 3 hours is treated with diluted hydrochloric acid. The crude desired product is collected by filtration and purified by crystallization in ethanol.

3-Chloro-2,4,5,6-tetrafluoropyridine (50.0 g) is dissolved in dry THF (500 mL) and cooled to 0xc2x0 C. A solution of lithium tert-butoxide (270 mL, 1.0 M in THF) is added dropwise over 50 minutes and the solution is then allowed to stir an additional 90 min. at 0xc2x0 C. before warming to room temperature. The reaction mixture is poured into hexanes (1000 mL) and filtered through a pad of Celite(copyright). After concentration via rotary evaporation, the liquid is applied to a column of silica gel in hexanes to isolate the desired compound.
Sodium acetate (12.75 g) and palladium on carbon (18.66 g, 10% Pd) are added to a solution of 4-tert-butoxy-3-chloro-2,5,6-trifluoropyridine (31.028 g) in THF (800 mL) and the mixture is placed under hydrogen (1 atm). The mixture is allowed to stir at room temperature for 48 h. The palladium is removed by filtration through a pad of Celite(copyright), which is washed with hexanes. After concentration, the liquid is applied to a column of silica gel in 5% ether in petroleum ether to isolate the desired compound.
n-Butyllithium (45.6 mL, 2.5 M in hexanes) is added via syringe to a solution of dry diisopropylamine (14.93 mL) in anhydrous THF (300 mL) under argon at xe2x88x9278xc2x0 C. and the mixture is allowed to stir 20 minutes. A solution of 4-tert-butoxy-2,5,6-trifluoropyridine (15.58 g) in dry THF (30 mL) is added. Methyl iodide (9.45 mL) is added via syringe and the cooling bath is removed. After stirring 90 minutes, the slurry is poured into a saturated aqueous ammonium chloride solution (250 mL) and is extracted twice with hexanes. The combined organic layers are washed with water and brine and dried over MgSO4. Evaporation of the solvent provided the desired compound.
Hydrazine monohydrate (16.6 mL) is added to a solution of 4-tert-butoxy-2,3,6-trifluoro-5-methylpyridine (13.19 g) in n-propanol (200 mL) and the resulting solution is refluxed under argon for 16 h. The mixture is cooled to room temperature and the solvent evaporated. The residue is redissolved in methylene chloride, washed with water, and dried over MgSO4. The desired product is obtained by evaporation of the solvent.
Crude 4-tert-Butoxy-2,5-difluoro-6-hydrazino-3-methylpyridine (from the run above) is dissolved in methanol (150 mL) and a 20% aqueous sodium hydroxide solution (32 mL) is added. Air is bubbled through the reaction mixture as it stirred for 48 h. The solvent is removed and the residue is redissolved in methylene chloride. This organic layer is washed once with water and is dried over MgSO4 and the solvent evaporated. The desired product is purified by chromatography using hexanes/ether 95/5 as solvent.
Dry diisopropylamine (12.0 mL) is dissolved in anhydrous THF (80 mL). The solution is cooled to xe2x88x9278xc2x0 C. and n-butyllithium (36.6 mL, 2.5 M in hexanes) is added. After 30 minutes, cyclopropylacetonitrile (3.6 g) is added in dry THF (20 mL). 4-tert-butoxy-2,5-difluoro-3-methyl-2-pyridine (7.37 g) in THF (20 mL) is then added. The mixture is allowed to stir 1 h at xe2x88x9278xc2x0 C. and 1 hr at room temperature before it is poured into a saturated aqueous ammonium chloride solution (150 mL) and extracted twice with ether. The combined organic layers are washed with brine, dried over MgSO4, and concentrated to give a yellow oil. The oil is applied to a column of silica gel in 20% ethyl acetate in hexanes to give the desired product.
2-(4-tert-Butoxy-5-fluoro-3-methyl-2-pyridinyl)cyclopropaneacetonitrile (10.5 g) is dissolved in neat trifluoroacetic acid (100 mL) and stirred 1 h at room temperature. The trifluoroacetic acid is then removed to give the desired product.
Crude 2-(4-Hydroxy-5-fluoro-3-methyl-2-pyridinyl)cyclopropaneacetonitrile from the previous reaction is dissolved in dichloromethane (150 mL) and anhydrous N,N-dimethylformamide (30.9 mL) is added followed by phosphorous oxychloride (3.7 mL). This mixture is stirred for 48 hours at room temperature, then poured into cold water (150 mL) and extracted with dichloromethane. The pH of the aqueous layer is raised to 7 with 1 N NaOH. The aqueous layer is extracted twice more with dichloromethane and the combined organic layers are washed once with water, dried over MgSO4, and concentrated. The desired product is purified by chromatography using hexanes/ethyl acetate 8/2 as solvent.
Hydrogen chloride gas is bubbled through a solution of 2-(4-chloro-5-fluoro-3-methyl-2-pyridinyl)cyclopropaneacetonitrile (2.91 g) in ethanol (9 mL) until the weight had increased by 3.56 g and heated to reflux. Water (0.32 mL) is added and the mixture is allowed to reflux 2 h before cooling to room temperature and adding water. The pH is adjusted to 7 with solid sodium bicarbonate and it is extracted with dichloromethane. The combined organic layers are washed with water, dried over MgSO4, and concentrated to give a yellow liquid which is purified by column chromatography on silica gel in 20% ethyl acetate in hexanes to give the desired product.
Ethyl 2-(4-chloro-5-fluoro-3-methyl-2-pyridinyl)cyclopropaneacetate (1.31 g) is dissolved in dry THF (10 mL). Lithium aluminum hydride (91.8 mg) is added to this solution and it is allowed to stir 1 h at room temperature. The reaction mixture is quenched with a saturated aqueous solution of sodium potassium tartrate (25 mL) and extracted with ether. The combined organic layers are dried with MgSO4 and concentrated to give the desired product.
2-(4-Chloro-5-fluoro-3-methyl-2-pyridinyl)cyclopropaneethanol is dissolved in dichloromethane (5 mL) and added to a solution of oxalyl chloride (0.51 mL) and dry DMSO (0.82 mL) in dichloromethane (12 mL) at xe2x88x9278xc2x0 C. After stirring 15 minutes, triethylamine (3.31 mL) is added and the mixture stirred another 5 minutes at xe2x88x9278xc2x0 C. and 10 minutes at 0xc2x0 C. The reaction is then quenched with water and extracted with dichloromethane. The combined organic layers are washed with water, dried over MgSO4, and concentrated to give the desired product.
Piperidine (1.14 mL), acetic acid (1.14 mL) and diethyl malonate (3.80 mL) are added to a solution of 2-(4-Chloro-5-fluoro-3-methyl-2-pyridinyl)cyclopropaneacetaldehyde in ethanol (40 mL) and the reaction mixture is heated at reflux under argon for 4 h. The solvents are removed and the residue is dissolved in ether. The ether layer is washed with water and brine, dried over MgSO4 and concentrated. The desired product is purified by chromatography using hexane/ethyl acetate as solvent.
A solution of Diethyl [(4-Chloro-5-fluoro-3-methyl-2-pyridinyl)cyclopropanemethyl-methylene]malonate (539.1 mg) in diphenyl ether (25 mL) is heated at 220xc2x0 C. for 45 minutes, then allowed to cool to room temperature. The desired product is isolated by chromatography using hexane then ethyl acetate as solvent.
b. Precursor Preparationxe2x80x947-Position Moiety:

A solution of methyl 3-(tert-butoxycarbonyl)-2,2-dimethyl-4-oxazolidinecarboxylate (4.91 g) is dissolved in toluene (40 mL) and cooled to xe2x88x9278xc2x0 C. To it a solution of diisobutylaluminum hydride (xe2x80x9cDIBALxe2x80x9d) (33.2 mL, 1 M) is added dropwise to maintain the internal temperature under xe2x88x9260xc2x0 C. After the addition, the resulting solution is stirred at xe2x88x9278xc2x0 C. for 30 min., and then slowly warmed to 0xc2x0 C. in 2 hrs. The mixture is quenched by addition of water. The organic layer is separated and the aqueous layer is extracted once with ethyl acetate. The combined extracts are dried over anhydrous MgSO4 and evaporated. The residue is purified by flash chromatography using ethyl acetate-hexanes.
To a solution of 3-(tert-butoxycarbonyl)2,2-dimethyl-4-oxazolidinecarboxaldehyde (6.5 g) in THF (26 mL) is added a solution of EtMgBr (42.5 mL, 1 M in THF) dropwise at xe2x88x9278xc2x0 C. After the addition, the resulting solution is allowed to warm to 0xc2x0 C. in 1.5 hr and water is added to quench the reaction. The mixture is partitioned between sat. NaCl solution and ethyl acetate (EtOAc). The organic layer is separated and the aqueous layer is extracted with EtOAc twice. The combined extracts are dried over MgSO4 and evaporated under reduced pressure. The crude product is purified by flash chromatography with EtOAc-Hexanes to give a colorless oil.
A solution of oxalyl chloride (2.08 mL) in dichloromethane (70 mL) is cooled in an acetone-dry ice bath and to it is added dimethyl sulfide (3.53 mL) dropwise to control the internal temperature under xe2x88x9265xc2x0 C. After stirring at that temperature for 5 min, a solution of 3-(tert-butoxycarbonyl)2,2-dimethyl-4-(1-hydroxy-propyl)-oxazolidine (5.15 g) in dichloromethane is added in such a rate to control the internal temperature under xe2x88x9265xc2x0 C. The resulting mixture is stirred at xe2x88x9278xc2x0 C. for 30 min, and triethylamine (13.8 ml) is added in one portion. Stirring is continued for additional 5 min. The cold bath is removed and the reaction temperature is allowed to rise to room temperature in 30 min. Water is added to quench the reaction. The organic layer is separated and the aqueous layer is extracted with dichloromethane twice. The combined extracts are washed with brine and dried over MgSO4 and evaporated under reduced pressure. The residue is purified by flash chromatography using EtOAc-Hexanes.
To a suspension of (CH3)3PPh3Br (8.59 g) in anhydrous THF (40 mL) is added t-BuOK (2.7 g) in one portion at room temperature. After stirring for 10 min, the yellow mixture is treated with a solution of 3-(tert-butoxycarbonyl)2,2-dimethyl-4-(1-oxo-propyl)-oxazolidine (4.12 g) in THF. The mixture is stirred for an additional 10 min. and is then partitioned between sat. NaCl solution and EtOAc. The organic layer is separated and the aqueous layer is extracted with EtOAc twice. The combined extracts are dried over MgSO4 and evaporated under reduced pressure. The residue is precipitated in ether and the formed white solid is removed by filtration. The filtrate is evaporated and the residue is purified by flash chromatography using EtOAc-Hexanes.
A solution of 3-(tert-butoxycarbonyl)2,2-dimethyl-4-(1-buten-2yl)-oxazolidine (3.25 g) and p-TsOH.H2O (0.484 g) in MeOH (100 mL) is heated at 50-60xc2x0 C. for 18 hr. After cooling, the solvent is evaporated to ⅓ of its volume and diluted with EtOAc. The mixture is washed with sat. NaHCO3 solution. The organic layer is separated and the aqueous is extracted with EtOAc two times. The combined extracts are dried over anhydrous MgSO4 and evaporated. The residue is purified by flash chromatography with EtOAc-Hexanes.
A solution of 2-tert-butoxycarbonylamino-3-methylene-pentanol (1.37 g), methanesulfonyl chloride (0.592 g) and triehylamine (1.06 mL) in dichloromethane (20 ml) is stirred at 20xc2x0 C. for 10 min., then is washed with a saturated solution of sodium bicarbonate followed by diluted HCl. The solvent is evaporated to afford the desired product.
A solution of 2-tert-butoxycarbonylamino-3-methylene-1-methanesulfonylyloxy-pentane (1.87 g) and allylamine (4.77 mL) dissolved in dichloromethane is heated at reflux for 2 hrs. The solution is washed with sat. NaHCO3. The organic layer is dried with anhydrous MgSO4 and evaporated under reduced pressure to give the diene product
A solution of 2-tert-butoxycarbonylamino-3-methylene-N-(2-propenyl)-pentylamine (1.62 g), trifluoroacetic anhydride (0.82 mL) and Et3N (0.89 mL) is stirred at  less than 10xc2x0 C. for 30 min. under argon. The mixture is washed with sat. NaHCO3, dried over anhydrous MgSO4 and evaporated. The residue is purified by flash chromatography using EtOAc-Hexanes.
2-tert-butoxycarbonylamino-3-methylene-N-(2-propenyl)-N-trifluoroacteyl-pentylamine (1.05 g) and Grub""s Ruthenium catalyst (0.247 g) are dissolved in dichloromethane (200 mL) and the solution is heated at reflux under argon for 20 hrs. The solvent is evaporated and the residue is purified by flash chromatography using EtOAc-Hexanes.
A mixture of 1,2,3,6-tetrahydro-3-tert-butoxycarbonylamino-4-ethyl-1-trifluoroacetyl-pyridine (0.865 g) and 10% Pd/C (0.086 g) in EtOH (35 mL) is subjected to the hydrogenation conditions at 1 atm H2 pressure for 24 hr. The solid is removed by filtration and the filtrate is evaporated. The crude product is purified by flash chromatography using EtOAc-Hexanes.
A mixture of Trans 3-tert-butoxycarbonylamino-4-ethyl-1-trifluoroacetyl-piperidine (0.43 g) and K2CO3 (0.94 g) in MeOH (20 mL) and H2O (5 mL) is heated at reflux for 30 min. The solid is removed by filtration and the filtrate is concentrated. The residue is partitioned between H2O and dichloromethane. The organic layer is separated and the aqueous layer is extracted with dichloromethane. The combined extracts are dried over anhydrous MgSO4 and evaporated.

Methyl acrylate (10 g) is dissolved in methanol (100 mL) and benzylamine (12.69 mL) is added. The solution is allowed to stir at room temperature for 24 hr. The reaction is concentrated and the residue is distilled (110-119xc2x0 C. at 4 mbar) to give the desired product.
xcex2-alanine, N-(benzyl)xe2x80x94, methyl ester (5 g), ditertbutyldicarbonate (5.65 g) and triethylamine (5.4 mL) are dissolved in dry methylene chloride and allowed to stir overnight. The reaction is washed with 3xc3x97water, dried over sodium sulfate, filtered and concentrated. The residue is purified by flash chromatography with 10% ethyl acetate/hexanes.
xcex2-alanine, N-benzyl-N-tert-butoxycarbonyl, methyl ester (8.3 g) is dissolved in toluene (125 mL) and cooled to xe2x88x9278xc2x0 C. Dibal (85.2 mL, 1 M) solution in toluene is added slowly keeping temperature below xe2x88x9270xc2x0 C. The reaction is then put in a constant temperature bath at xe2x88x9240xc2x0 C. for 2 hr and then cooled back down to xe2x88x9270xc2x0 C. The reaction is quenched with methanol (85 mL) and allowed to warm to room temperature. After 1 hr of stirring at room temperature the reaction is filtered through celite and the salts are washed with methanol. The combined filtrates are concentrated and the residue is dissolved in methylene chloride. The organic layer is washed with 2xc3x971 N HCl and 1xc3x97brine. The organic layer is dried over sodium sulfate, filtered and concentrated. The residue is purified by flash chromatography with 12.5% ethyl acetate/hexanes.
Oxalyl Chloride (2.07 mL) is dissolved in methylene chloride and cooled to xe2x88x9278xc2x0 C. DMSO (3.2 mL) is added keeping the temperature below xe2x88x9260xc2x0 C. The reaction is allowed to stir for 20 min. and then N-benzyl-3-tert-butoxycarbonylamino-1-propanol (3 g) in methylene chloride is added keeping the temperature below xe2x88x9260xc2x0 C. The reaction is allowed to stir for 30 min., then triethylamine (13.2 mL) is added, allowed to warm to room temperature and stir for 1 hr. The reaction is diluted with methylene chloride and water. The layers are separated and the organic layer is washed twice with 1 N HCl and once with brine. The organic layer is dried over sodium sulfate, filtered and concentrated. The residue is purified by flash chromatography.
N-benzyl-3-tert-butoxycarbonylamino-1-propanal (1.46 g) is dissolved in toluene and methyl (triphenylphosphoranylidene)acetate (2.04 g) is added. The reaction is heated to reflux and allowed to stir overnight. After concentration, the residue is triturated with hexanes and filtered washing solids with hexanes. The filtrate is concentrated and the residue is purified by flash chromatography with 25% ethyl acetate/hexanes.
Methyl,N-benzyl-5-tert-butoxycarbonylamino-2-pentenoate (1.68 g) is dissolved in methylene chloride and cooled to 0xc2x0 C. Trifluoroacetic acid (4 mL) is added to make a 20% solution and is allowed to warm to room temp. The reaction is complete in 15 min. and diluted with methylene chloride. The reaction is washed with 3xc3x97sat. sodium bicarbonate and 1xc3x97brine. The methylene chloride is dried over sodium sulfate, filtered and concentrated to give the desired product.
Methyl,N-benzyl-5-amino-2-pentenoate (1.16 g) is dissolved in ethanol (12 mL) and 2-benzoyloxy-1-nitro-ethane (1.55 g) is added. The solution is allowed to stir at room temperature overnight and is then concentrated. The residue is dissolved in methylene chloride and washed 3 times with 100 mL sat. sodium bicarbonate and once with brine. The organic layer is dried over sodium sulfate, filtered and concentrated. The residue is purified by flash chromatography with 25% ethyl acetate/hexanes.
Trans N-benzyl-4-(methylacetate-2-yl)-3-nitro-piperidine (0.67 G) is dissolved in THF (16 mL) and Raney nickel (100 mg) is added. The reaction is allowed to stir under hydrogen overnight. The reaction is not complete, so additional Raney nickel (100 mg) is added and allowed to stir under hydrogen for 8 hr. The reaction is filtered through Celite(copyright) and the filtrate is concentrated to give the desired product.
Trans N-benzyl-4-(methylacetate-2-yl)-3-amino-piperidine (0.863 g) and ditertbutyldicarbonate (0.72 g) are dissolved in methylene chloride. Triethylamine (0.68 mL) is added and allowed to stir overnight. The reaction is diluted with methylene chloride and washed with 2xc3x97water. The organic layer is dried over sodium sulfate filtered and concentrated. The residue is purified by flash chromatography with 25% ethyl acetate/hexanes.
Trans N-benzyl-4-(methylacetate-2-yl)-3-tertbutoxycarbonylamino-piperidine (0.45 g) is dissolved in THF (10 mL) and cooled to xe2x88x9278xc2x0 C. A 1 M solution of lithium aluminum hydride in THF (7.44 mL) is added in four aliquots and allowed to stir for 45 min. between additions. The reaction is allowed to stir for 2 hr and is then quenched with water 15% NaOH (0.7 mL). The quenched reaction is filtered and the salts are washed with THF. The salts are suspended in THF and heated to reflux. The salts are filtered hot and washed with THF. The combined filtrates are concentrated and the residue is purified by flash chromatography with 3 to 5% methanol/methylene chloride.
Trans N-benzyl-4(2-hydroxy-ethyl)-3-tertbutoxycarbonylamino-piperidine (0.19 g) is dissolved in methanol (2 mL) and acetic acid (1 drop). Palladium hydroxide (0.05 g) is added and allowed to stir overnight under hydrogen. The reaction is filtered through Celite(copyright) and the filtrate is concentrated to give the desired product, Precursor G.
Trans N-benzyl-4-(2-hydroxy-ethyl)-3-tertbutoxycarbonylamino-piperidine (0.21 g) is dissolved in dichloromethane and diethylaminosulfur trifluoride (0.5 mL) is added. The solution is allowed to stir at room temperature for 3 hr and is quenched with ethanol. After one hour at room temperature, the solution is washed with brine and the solvent evaporated. The desired product is obtained by flash chromatography with 3 to 5% methanol/methylene chloride.
Trans N-benzyl-4-(2-fluoro-ethyl)-3-tertbutoxycarbonylamino-piperidine (0.09 g) is dissolved in methanol (1 mL) and acetic acid (1 drop). Palladium hydroxide (0.025 g) is added and allowed to stir overnight under hydrogen. The reaction is filtered through Celite(copyright) and the filtrate is concentrated to give the desired product, Precursor H.
c. Final Product Preparation